"It's not a question of having water just up your nose, as it has to go all the way up to the roof of your nose." Dr. Raoult Ratard

The St. Bernard Parish water system has tested positive for a rare brain-eating amoeba, the federal Centers for Disease Control and Prevention confirmed, about a week after St. Bernard Parish government officials assured the public that the parish was taking every precaution possible to flush out its water system.

The CDC has confirmed the presence of the Naegleria fowleri amoeba in four locations of parish's water system in Violet and Arabi, the Louisiana Department of Health and Hospitals said Thursday (Sept. 12).

"While the water is safe to drink, there is a risk if the amoeba enters the nose," State Health Officer Jimmy Guidry said Thursday. "There are basic precautions that families can take -- such as chlorinating their pools and avoiding getting water in their noses -- to protect themselves, though infection from this amoeba is very rare."

The DHH announced last week that a 4-year-old Mississippi child visiting a St. Bernard Parish home died from primary amebic meningoencephalitis, a brain infection that leads to the destruction of brain tissue. It confirmed that the boy likely contracted the infection after playing on a Slip 'n Slide for a long time and having the warm, untreated water go up his nose.

"If you take a bath, do not put your head under the water completely. To take a shower, it is no problem," said Louisiana State Epidemiologist Dr. Raoult Ratard. "If you take a shower and you put the shower head right up your nose, that's not a good idea -- but nobody does that.

"It's not a question of having water just up your nose, as it has to go all the way up to the roof of your nose," Ratard said. "I take a shower every day and I never have water going up all the way to the ceiling of the nose. The water has to go all the way up, and you can feel it, because it burns if water goes way, way up there."

Ratard said diving into big, well-chlorinated swimming pools should be fine, as well. The problem generally is with smaller pools that might be poorly chlorinated, he said.

Primary amebic meningoencephalitis -- often abbreviated as PAM -- is a rare infection that has been associated with two deaths traced to water in Louisiana in 2011, according to the DHH.

And because some parish water samples showed low residual levels of chlorine, the DHH sent additional water samples to the CDC for testing last week as St. Bernard began flushing its water lines with additional chlorine, as a precautionary measure.

"We know that chlorine kills Naegleria fowleri, which is why it was critical that the parish proactively began flushing its water system with additional chlorine last week," DHH Assistant Secretary for Public Health J.T. Lane said Thursday. "The parish will continue this action until it raises chlorine residuals to recommended levels, and this process will continue for several weeks.

"DHH is working with parish officials to provide assistance and support to the parish's staff to ensure that chlorine levels are being monitored daily."

Naegleria fowleri amoeba.

DHH scientists pulled samples from hydrants and faucets that connected directly to the water lines throughout the parish. Hundreds of liters of water were filtered to capture any amoebae that might be present in the water, according to the DHH.

In the 10 years from 2001 to 2010, only 32 infections were reported in the United States, according to the CDC. Of those cases, 30 people were infected by contaminated recreational water and two people were infected by water from a drinking water supply.

Only about 120 U.S. cases — almost all of them deaths — have been reported since the amoeba first was identified in the early 1960s, according to the CDC. About three deaths are reported each year, on average. In August, a 12-year-old Florida boy died after contracting the infection.

Earlier in August, a 12-year-old Arkansas girl survived the infection after being given an experimental breast cancer drug and having her body temperature lowered. Officials believe she is only the third person to survive this infection.

The DHH states that people cannot contract the infection by drinking contaminated water, because stomach acid will kill the amoeba. Naegleria fowleri -- which can cause encephalitis -- infects people by entering the body through the nose.

In 2011, a 28-year-old St. Bernard Parish man died after using infected tap water in a device called a neti pot. It's a small teapot-shaped container used to rinse out the nose and sinuses with salt water to relieve allergies, colds and sinus trouble.

That same year, a 51-year-old DeSoto Parish woman died from the same infection after also using tap water in a neti pot and becoming infected with the deadly amoeba.

Exposure to Naegleria fowleri typically occurs when people go swimming or diving in warm freshwater lakes and rivers. In rare instances, Naegleria fowleri infections may also occur when contaminated water from other sources, such as inadequately chlorinated swimming pool water or tap water heated less than 116.6 degrees, enters the nose when people submerge their heads or when people irrigate their sinuses with devices such as a neti pot. According to the CDC, people can reduce the risk of a Naegleria fowleri infection by limiting the amount of water going up one’s nose.

Initial symptoms of primary amebic meningoencephalitis start one to seven days after infection. The symptoms include headache, fever, nausea, vomiting and a stiff neck.

Later symptoms include confusion, lack of attention to people and surroundings, loss of balance, seizures and hallucinations. After symptoms start, the disease progresses rapidly and usually causes death within one to 12 days.

Do not allow water to go up your nose or sniff water into your nose when bathing, showering, washing your face or swimming in small hard plastic/blow-up pools.

Do not jump into or put your head under bathing water (in bathtubs, small hard plastic/blow-up pools). Instead, walk or lower yourself in.

Do not allow children to play unsupervised with hoses or sprinklers, as they may accidentally squirt water up their noses. Avoid slip-n-slides or other activities where it is difficult to prevent water going up the nose.

Do run bath and shower taps and hoses for five minutes before use to flush out the pipes. This is most important the first time you use the tap after the water utility raises the disinfectant level.

Do keep small hard plastic/blow-up pools clean by emptying, scrubbing and allowing them to dry after each use.

Do use only boiled and cooled, distilled or sterile water for making sinus rinse solutions for neti pots or performing ritual ablutions.

Do keep your swimming pool adequately disinfected before and during use.

Do place hoses directly into the skimmer box of swimming pools and ensure that the filter is running.

Do not top off by placing the hose in the body of the swimming pool.

Residents should continue these precautions until extensive testing no longer detects the amoeba in the water system, the DHH stated on Thursday. The DHH said that they would announce when that occurs.